Display 2 different validation messages in a single field

Gurus,

Need some help on displaying 2 different validations on the status field in the service request object.
My existing validation is
NOT(PRE ('<plSCD_Status_ITAG>') <> [<plSCD_Status_ITAG>] AND ([<plSCD_Status_ITAG>]=LookupValue("OCC_CUST_LOV_SR_20", "Scoping") OR [<plSCD_Status_ITAG>]=LookupValue("OCC_CUST_LOV_SR_20", "Implement Fix") OR [<plSCD_Status_ITAG>]=LookupValue("OCC_CUST_LOV_SR_20", "Verify Change")) AND UserValue('<EMailAddr>') <> '***@***.com')
this will prevent any users other than the specified email id  to set the status of the service request to the above mentioned values.

my requirement is when the status of the service request is closed, the account name should not begin with Channel.